.TH "LIGHTNING-CHECKMESSAGE" "7" "" "" "lightning-checkmessage"
.SH NAME
lightning-checkmessage - Command to check a signature is from a node
.SH SYNOPSIS

\fBcheckmessage\fR \fImessage\fR \fIzbase\fR [\fIpubkey\fR]

.SH DESCRIPTION

The \fBcheckmessage\fR RPC command is the counterpart to
\fBsignmessage\fR: given a node id (\fIpubkey\fR), signature (\fIzbase\fR) and a
\fImessage\fR, it verifies that the signature was generated by that node
for that message (more technically: by someone who knows that node's
secret)\.


As a special case, if \fIpubkey\fR is not specified, we will try every
known node key (as per \fIlistnodes\fR), and verification succeeds if it
matches for any one of them\.  Note: this is implemented far more
efficiently than trying each one, so performance is not a concern\.

.SH RETURN VALUE

On correct usage, an object with attribute \fIverified\fR will be
returned\.


If \fIverified\fR is true, the signature was generated by the returned
\fIpubkey\fR for that given message\.  \fIpubkey\fR is the one specified as
input, or if none was specified, the known node which must have
produced this signature\.


If \fIverified\fR is false, the signature is meaningless\.  \fIpubkey\fR may
also be returned, which is they \fIpubkey\fR (if any) for which this
signature would be valid\.  This is usually not useful\.

.SH AUTHOR

Rusty Russell \fI<rusty@rustcorp.com.au\fR> is mainly responsible\.

.SH SEE ALSO

\fBlightning-signmessage\fR(7)

.SH RESOURCES

Main web site: \fIhttps://github.com/ElementsProject/lightning\fR